3 Answers by Expert Tutors

The speed of light in vacuum is equal to the product of the index of refraction and the speed of light through that substance. c = n1v1 = n2v2 , since the frequency is constant then the product of wavelength through a medium and its index of refraction in that medium is equal to its wavelength in new medium and its new index of refraction, n1x1 = n2x2. The answer is A, 2400/1.5 = 1600.